My group is generally great with NPCs, whether I'm DMing or playing. However, one player with a mischievous streak and a short attention span sometimes just does stuff for the heck of it. The party usually sorts this out themselves. Example:
In a recent Ravenloft game, our group was trying to spring a prisoner from a tower in the middle of a town. The region was known for having a reaving Red Dragon, so we waited until night, tossed a bunch of alchemist fire jugs on stone buildings and had a summoned griffon let its silhouette be seen against the night sky. The guards distracted we retreived the prisoner and headed out of town, lobbing alchemist fire at more stone buildings. As we were a generally (except for the one player) good-aligned group, we made sure no one would throw any on anything actually flammable or hurt any people.
Our deviant, naturally tried lobbing some at some fleeing innocents, which my cleric of Odin healed. My cleric is pretty...hardcore...let's say, when it comes to morality. He had already set himself on fire to buy the party time to flee from some swarms and so felt he had earned the right to do the following:
That night at camp my cleric woke Deviantboy up by dashing a jug of alchemist fire on him. As DB woke, my cleric basically said, "As you have put others to the flame, so does this flame judge you. Survive, and you may continue to live." Luckily, I won the initiative and readied an action; if he acted hostile, he was gonna catch a Hold Person. Probably needless to say, one Hold Person and a coup de grace later, we had one less impulsive tard in the group. Harsh? Maybe. But, strangely enough, the other players didn't have a problem with it at all.
